Bilge pump rubbers

[blackbeard]

That is, the diaphragm and valves.
Pump is tested from time to time, was OK a couple of months ago. It, like the boat, is about 12 years old. It's the usual manual pump.
Makers suggest the rubber bits should be replaced every 3 years - is this really necessary? How long to the things last normally? I have never seen it suggested (other than by the pump maker) that the rubbers have a limited life ...

What does the forum think?

 

[cimo]

you are talking about the whale/henderson manual types?

Have a spare diaphragm on board and replace when necessay is my policy.
The valves are nothing more than circular plastic flaps.

The current diaphragm in my bilge pump was manufactured from the ships hot water bottle (two years ago now). It cost me around 2.99 to replace the hwb. I did get the official repair kit this year though - 28.00 I think (why do they put a full set of nuts & bolts in the repair kit?).

Keeping the rubber soft and prevent it from drying out is the trick (I'm using vaseline) Also, restricting pumping action to just within full stroke limits can reduce stress on the diaphragm & add longevity.